Australian rules football (also known as football, "footy" or "Aussie Rules" in areas where it is the predominant winter sport) is a game played between two teams of 18 players, generally played on cricket ovals during the winter months.

Football competitions run approximately from March to August, with finals being held in September. Pre-season competitions sometimes begin as early as late February. The summer months mostly belong to cricket, usually played on the same grounds. In the past, many elite-level footballers played representative cricket, but the increasingly professional nature of the game made this impossible by the 1980s. Many amateur players still play both. Unlike most soccer competitions, there are no separate "league" and "cup" trophies. The teams that occupy the highest positions (usually four in most amateur leagues, but up to eight in the AFL) play off in the "semi-knockout" (under most systems, the very highest-finishing teams usually get a second chance if they lose their first final) finals series, with the two successful teams meeting in the Grand Final.

The game is a fast-paced combination of speed, athleticism, skill and physical toughness. Players are allowed to tackle the player with the ball and impede opposition players from tackling their teammates, but not to deliberately strike an opponent (though pushing the margins of these rules is often a substantial part of the game). Like most team sports, tactics are based around trying to get the ball, then - through a combination of running with the ball, handballing/handpassing (punching the ball) and kicking - deliver it to a player who is within range of goal. Because taking a mark entitles the player to a free kick, a common tactic is to attempt to kick the ball on the full (without bouncing) to a teammate who is within kicking range of goal. In this situation packs often form, and spectacular high marks (where players launch themselves off opponents' backs high in the air to mark the ball) are common.

It was said that Australian football was inspired by the ball games of the local Aboriginal people in western Victoria. However, whilst the Aborigines did play a sport called Marn Grook, which used a ball made out of kangaroo hide and which included features resembling the high marking in Australian Rules, there is considerable debate over the connection between the two. H.A. Harrison had grown up in an area of Victoria near present day Moyston where he may have played Marn Grook with local Aborigines. It is considered more likely, however, that he drew inspiration from varieties of football brought to Victoria by immigrants from Britain and Ireland.

In the late 1980s, a strong interstate interest in the game led to a more national competition and the VFL changing its name to the Australian Football League (AFL) in 1989 and admitting non-Victorian clubs. The AFL is the 16 club elite-level competition in the game.

At the elite level, the game still retains some touches from its inter-suburban roots. Players run on to the field through a crepe paper banner depicting some message (for instance, congratulating players on a milestone number of games) constructed by volunteer supporter groups at the mostly member-owned clubs. All clubs have a team song, most composed in the 1940s or aping the musical style.

Perhaps the most notable of the other leagues are the South Australian National Football League (SANFL) and the Western Australian Football League (WAFL). Prior to the birth of the AFL, these two leagues were every bit as important as the VFL - these three leagues being the premier football league in each of the three premier football states. Although the VFL was generally accepted as the strongest league, clubs from all three leagues frequently played each other on an even footing in challenge matchs and occasional nationwide club competitions that were basically precursors to the AFL. However, with the introduction of the AFL, the state leagues rapidly declined to a secondary status.

The VFA, still in existence a century after the original VFL schism, changed its name to the Victorian Football League soon after the VFL changed its name to the Australian Football League.

A series of hybrid matches between Australia's best and a representative Gaelic football team from Ireland have been staged on an yearly basis. The rules (called "International Rules") are a compromise between the two codes, using a round ball and a rectangular field but allowing the fierce tackling of the Australian code. The series have remained evenly matched with the Irish using speed and athleticism, and the Australians strength and power - both inherent skills in their respective codes. This contrast of skills has created exciting contests that have been a hit with spectators.

Several Irish gaelic footballers have been recruited to play in Australia, most notably Brownlow medallist Jim Stynes, Sean Wight and more recently Tadhg Kennelly.

The inaugural Australian Rules International Cup was held in Melbourne, Australia in 2002. 11 teams made up exclusively of foreign nationals played a series of matches, with, in a surprise result, Ireland defeating Papua New Guinea in the final.